OK I finally got my m-03 running and all upgraded. It is set up pretty much with every tamiya upgrade and bearings, ball diff, universals. I also have a m-01. both of these I have only had the m-01 for 2 weeks and the m-03 for less than one. I put the same gear in my m-03 to compare to the m-01. same motor, battery, esc, reciever etc. the m-01 is alot faster than the m-03. And I cant figure out why. is the gearing different? I can't pinpoint a huge friction difference. the m-01 has the stock gear diff. the only thing I can figure is the m-01 is used so the grears are very well worn in. The m-03 is new with the ball diff. could this cause enough friction to cause it to be a slower vehicle? Sort of dissapointed the m-01 was so fast and handled pretty well. the m-03 handles even better but the speed lacks. I ran a 20T pinion in both. I also wore through the stock tires in one battery. I guess it needs an alignment.